Add/Remove Items

Adding items to dictionary:

There are two ways to add items to a dictionary.

I. Create a new key and assign a value to it:

Example:

info = {'name':'Maxon', 'age':25, 'eligible':True}
print(info)
info['DOB'] = 1999
print(info)

Output:

{'name': 'Maxon', 'age': 25, 'eligible': True}
{'name': 'Maxon', 'age': 25, 'eligible': True, 'DOB': 1999}

 

II. Use the update() method:

The update() method updates the value of the key provided to it if the item already exists in the dictionary, else it creates a new key-value pair.

Example:

info = {'name':'Maxon', 'age':25, 'eligible':True}
print(info)
info.update({'age':26})
info.update({'DOB':2001})
print(info)

Output:

{'name': 'Maxon', 'age': 25, 'eligible': True}
{'name': 'Maxon', 'age': 26, 'eligible': True, 'DOB': 1999}

 

 

Removing items from dictionary:

There are a few methods that we can use to remove items from dictionary.

 

clear(): The clear() method removes all the items from the list. 

Example:

info = {'name':'Maxon', 'age':25, 'eligible':True}
info.clear()
print(info)

Output:

{}

 

pop(): The pop() method removes the key-value pair whose key is passed as a parameter.

Example:

info = {'name':'Maxon', 'age':25, 'eligible':True}
info.pop('eligible')
print(info)

Output:

{'name': 'Maxon', 'age': 25}

 

popitem(): The popitem() method removes the last key-value pair from the dictionary.

Example:

info = {'name':'Maxon', 'age':25, 'eligible':True, 'DOB':2001}
info.popitem()
print(info)

Output:

{'name': 'Maxon', 'age': 25, 'eligible': True}

 

apart from these three methods, we can also use the del keyword to remove a dictionary item. 

Example:

info = {'name':'Maxon', 'age':25, 'eligible':True, 'DOB':2001}
del info['age']
print(info)

Output:

{'name': 'Maxon', 'eligible': True, 'DOB': 2001}

 

If key is not provided, then the del keyword will delete the dictionary entirely.

Example:

info = {'name':'Maxon', 'age':25, 'eligible':True, 'DOB':2001}
del info
print(info)

Output:

NameError: name 'info' is not defined